A draw-bar assembly is often provided on a vehicle for towing trailers and the like. A conventional draw-bar assembly, generally known as a hitch, includes a draw-bar and a coupling device, such as a hitchball. With reference to FIG. 1, hitch 2 generally includes a hitchball 3 having a pair of opposed ball flats 4 and a shank 5 extending therefrom, and a draw-bar 6, having at one end 6a a hole 7 defined therethrough and the other end extending from the vehicle. To assemble hitch 2, shank 5 is inserted into hole 7 and a nut 8 is threaded onto the portion of shank 5 that extends through hole 7. To sufficiently tighten nut 8 a relatively high amount of torque is required. Typically, the installer must use two wrenches simultaneously to accomplish proper tightening. One wrench is used to tighten nut 8 and a second wrench is engaged with the opposed ball flats 4 to hold hitchball 3 in fixed rotational position. Such an operation is difficult for one person to perform, and often cannot be done by a single person.